Tools

"... In this paper we propose a formalism for the specification of systems built from interacting components. We define a notion of a system model consisting of a categorical diagram of models for individual components. For such diagram models we propose a logic in which it is possible to specify both th ..."

In this paper we propose a formalism for the specification of systems built from interacting components. We define a notion of a system model consisting of a categorical diagram of models for individual components. For such diagram models we propose a logic in which it is possible to specify both the temporal and the structural aspects of component configurations by freely interleaving temporal operators of the branching-time temporal logic with the constructs from the first-order logic. In particular, it is possible to describe dynamic system reconfiguration, for instance the creation or termination of system components. We formalise the diagram logic as an institution and provide an example specification.

"... We present a semantic model and a logic for systems of concurrent components. Following the categorical approach, we define a category of component models in which limits can be used to construct systems from simpler components. A novel idea is to use diagrams in this category, not just limit object ..."

We present a semantic model and a logic for systems of concurrent components. Following the categorical approach, we define a category of component models in which limits can be used to construct systems from simpler components. A novel idea is to use diagrams in this category, not just limit objects, as models for the logic. The resulting “diagram logic ” allows one to specify both behavioural and structural aspects of systems: temporal operators and structural predicates can be freely interleaved. As in first-order logic, system components can be quantified over, bound to variables and classified by predicates. There is a price we must pay for the expressive power of the logic: the set of valid formulae is not recursively enumerable. 1